Once Upon a Time Season 3, Episode 7 ("Dark Hallow") will finally return us to Storybrooke, thanks to Ariel's world-hopping mermaid abilities. But what will happen when she shows up in Storybrooke looking for help? We've gathered all of the biggest hints and spoilers about the episode right here, so you can prepare for Sunday's action. Read spoilers at your own risk! For more on Wetpaint Entertainment's philosophy on spoilers, click here.